In the past engine coolant radiators for sports cars have been located within an inlet air stream duct to the engine compartment. In aerodynamically configured front ends of such vehicles the radiator is tilted from the vertical to conform to a reduced vertical space within the underhood space of the vehicle. Such disposition of the radiator is required not only to fit a limited underhood space but is also required to locate the radiator within an inlet air stream duct characterized by having an inlet entering the engine compartment through the bottom of the vehicle front end rather than through a front radiator.
While the radiator is located at an angle to the inlet air stream the tubes and air centers of the radiator define air flow passages through the radiator which are not parallel to the incoming airflow through the bottom inlet. Accordingly, the tubes offer more resistance to flow than in the case of radiators vertically disposed downstream of a front grill. Increased pressure drop results with a loss in heat exchange efficiency.
Other radiators are known which are located in duct systems of a motor vehicle. U.S. Pat. No. 4,690,204 discloses an intercooler located in a rear engine vehicle. The intercooler is tilted from the vertical to conform to a limited rear space in the vehicle. The tubes of the intercooler are conventionally oriented. U.S. Pat. No. 4,362,208 discloses a truck radiator which is disposed in various tilted dispositions within a cooling duct. The tubes of the truck radiator are conventionally oriented within the cooling duct.
In none of the prior art configurations is the tilted radiator provided with tubes which are in turn tilted to conform air passages within the radiator to be parallel to the incoming airflow across the radiator.